<?php

/*
 * This file is part of SwiftMailer.
 * (c) 2004-2009 Chris Corbyn
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

/**
 * A collection of MIME headers.
 *
 * @package    Swift
 * @subpackage Mime
 * @author     Chris Corbyn
 */
interface Swift_Mime_HeaderSet extends Swift_Mime_CharsetObserver
{
	/**
	 * Add a new Mailbox Header with a list of $addresses.
	 *
	 * @param string $name
	 * @param array|string $addresses
	 */
	public function addMailboxHeader($name, $addresses = null);

	/**
	 * Add a new Date header using $timestamp (UNIX time).
	 *
	 * @param string $name
	 * @param integer $timestamp
	 */
	public function addDateHeader($name, $timestamp = null);

	/**
	 * Add a new basic text header with $name and $value.
	 *
	 * @param string $name
	 * @param string $value
	 */
	public function addTextHeader($name, $value = null);

	/**
	 * Add a new ParameterizedHeader with $name, $value and $params.
	 *
	 * @param string $name
	 * @param string $value
	 * @param array $params
	 */
	public function addParameterizedHeader($name, $value = null, $params = array());

	/**
	 * Add a new ID header for Message-ID or Content-ID.
	 *
	 * @param string $name
	 * @param string|array $ids
	 */
	public function addIdHeader($name, $ids = null);

	/**
	 * Add a new Path header with an address (path) in it.
	 *
	 * @param string $name
	 * @param string $path
	 */
	public function addPathHeader($name, $path = null);

	/**
	 * Returns true if at least one header with the given $name exists.
	 *
	 * If multiple headers match, the actual one may be specified by $index.
	 *
	 * @param string $name
	 * @param integer $index
	 *
	 * @return boolean
	 */
	public function has($name, $index = 0);

	/**
	 * Set a header in the HeaderSet.
	 *
	 * The header may be a previously fetched header via {@link get()} or it may
	 * be one that has been created separately.
	 *
	 * If $index is specified, the header will be inserted into the set at this
	 * offset.
	 *
	 * @param Swift_Mime_Header $header
	 * @param integer $index
	 */
	public function set(Swift_Mime_Header $header, $index = 0);

	/**
	 * Get the header with the given $name.
	 * If multiple headers match, the actual one may be specified by $index.
	 * Returns NULL if none present.
	 *
	 * @param string $name
	 * @param integer $index
	 *
	 * @return Swift_Mime_Header
	 */
	public function get($name, $index = 0);

	/**
	 * Get all headers with the given $name.
	 *
	 * @param string $name
	 *
	 * @return array
	 */
	public function getAll($name = null);

	/**
	 * Return the name of all Headers
	 *
	 * @return array
	 */
	public function listAll();

	/**
	 * Remove the header with the given $name if it's set.
	 *
	 * If multiple headers match, the actual one may be specified by $index.
	 *
	 * @param string $name
	 * @param integer $index
	 */
	public function remove($name, $index = 0);

	/**
	 * Remove all headers with the given $name.
	 *
	 * @param string $name
	 */
	public function removeAll($name);

	/**
	 * Create a new instance of this HeaderSet.
	 *
	 * @return Swift_Mime_HeaderSet
	 */
	public function newInstance();

	/**
	 * Define a list of Header names as an array in the correct order.
	 *
	 * These Headers will be output in the given order where present.
	 *
	 * @param array $sequence
	 */
	public function defineOrdering(array $sequence);

	/**
	 * Set a list of header names which must always be displayed when set.
	 *
	 * Usually headers without a field value won't be output unless set here.
	 *
	 * @param array $names
	 */
	public function setAlwaysDisplayed(array $names);

	/**
	 * Returns a string with a representation of all headers.
	 *
	 * @return string
	 */
	public function toString();
}
